1. Field
Example embodiments relate to a soft-start control of a power conversion device, for example, to a method and apparatus for reducing an inrush current inflowing from an external power source during an initial transient state.
2. Description of the Related Art
Inrush current may refer to the maximum, instantaneous current inflowing from an external power source when a power conversion device is turned on. For example, a relatively large difference between a band-gap voltage that is internally generated and a voltage of an output capacitor of a power conversion device may exist in an initial state. As a result, a controller of the power conversion device may charge the output capacitor by a relatively large current. This relatively large current may be the result of an inrush current inflowing from the external supply source. The inrush current may have a negative influence upon the reliability of the power conversion device and peripheral circuits, for example. To reduce the effects of inrush current, a reference voltage of the controller may be linearly increased such that a difference between the reference voltage and the voltage of the output capacitor may be decreased. However, a gain and a bandwidth of the controller may be difficult to control because the gain and the bandwidth are lowered due to the relatively low voltage level in the initial state of the power conversion device.